I used four ball-bearing drawer slides that are commonly found in office furniture such as filing cabinets and desk drawers. These operate very smoothly, have no lateral play, are available in several lengths and are quite easy to find at home centres (I purchased mine from The Home Depot).
|one vertical tower showing the drawer slides partially extended|
|the vertical towers; colour coding is to facilitate setup and packing so I know which piece goes where|
|The vertical towers inserted into the base; additional information about the base will be contained in Part 3|
One large closed hook is fastened on the upper portion of each tower, to which is attached one end of a large turnbuckle. The lower end of the turnbuckle is fastened to the lower portion of the tower. The turnbuckles I purchased have a lock nut at each end, helpful but not mandatory. I purchased these from Princess Auto.
There are additional, smaller turnbuckles that pass between two hooks mounted to the end of the base and to the tower. The purpose of these turnbuckles is to make fine adjustments to the inward-outward position of the towers so that the bridge is positioned with perfect clearance from end to end – too sloppy and there will be a “pothole” in the track, too snug and the bridge won’t close all the way. These turnbuckles are adjusted as part of the final setup.
The lower end of the turnbuckle is positioned in an open hook located at the base of each tower – the turnbuckle needs to be able to be removed from the bottom hook for transporting.
To be continued...